how to install busybox in Nexus S(JellyBean)

 busybox.zip   1. download busybox from :

Currently, the latest is 1.19.0:

$ wget 1.19.0/busybox-armv6l

$ mv busybox-armv6l busybox

2. you need make the directory/file tree like this:

$ tree

.

├── META-INF

│   └── com

│       └── google

│           └── android

│               ├── update-binary

│               └── updater-script

└── system

    └── bin

        └── busybox

2.1 put the download busybox to ./system/bin/busybox

2.2 ./META-INF/com/google/android/update-binary is exe file to run ths updater-script, you can get it from other update.zip

2.3 Below is the content in ./META-INF/com/google/android/updater-script

$ cat META-INF/com/google/android/updater-script

---------------8<----------------8<-------------------

ui_print("Busybox 1.19.0 for Android 2.0-4.1 arm");

ui_print("Mounting system...");

run_program("/sbin/busybox", "mount", "/system");

ui_print("Deleting old files...");

delete("/system/bin/busybox","/system/xbin/busybox");

ui_print("Copying files...");

package_extract_dir("system", "/system");

ui_print("Fixing permissions...");

set_perm(0, 0, 06755, "/system/bin/busybox");

ui_print("Symlinking...");

symlink("/system/bin/busybox", "/system/xbin/busybox");

ui_print("Unmounting system...");

run_program("/sbin/busybox", "umount", "/system");

ui_print("Installation complete!");

---------------8<----------------8<-------------------

3. zip the files

$ zip -r ../busybox.zip *

4. signed the zip file

4.1 make the signed key:

$ keytool -genkey -v -alias mw_apk_signed_key -keyalg RSA -keysize 2048 -validity 10000 -keystore michaelwu.keystore

4.2 sign it

$ jarsigner -verbose -keystore michaelwu.keystore /path/to/busybox.zip mw_apk_signed_key 

5. install it

5.1 upload it to phone

$ adb push /path/to/busybox.zip /mnt/sdcard/

5.2 reboot it to recovery mode (press Volume+ and Power key)

If you get error in recovery mode, this might help. (to update the recovery image)

$ sudo fastboot flash recovery recovery-twrp-2.2.0-crespo.img

5.3 then install the busybox.zip from sdcard

5.4 done!